Heat-dissipating assembly

ABSTRACT

A heat-dissipating assembly includes a body and a bottom plate. The body has a heat-absorbing portion. The interior of the heat-absorbing portion is provided with a chamber covered by the bottom plate. The chamber has an evaporating region for generating a high pressure, and a condensing region for generating a low pressure. The pressure gradient between the evaporating region and the condensing region is used to drive the circulation of liquid/vapor phase of a working fluid. With this structure, heat can be conducted rapidly without providing any wick structure.

This application claims the priority benefit of Taiwan patentapplication number 099123950 filed on Jul. 21, 2010.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a heat-dissipating assembly, and inparticular to a heat-dissipating assembly which is capable of driving aworking fluid to conduct the heat without providing a wick structure andthe manufacture cost thereof is reduced greatly.

2. Description of Prior Art

Currently, since highly-advanced manufacturing processes have beendeveloped in the electronic semiconductor industry, electronicapparatuses are made more and more compact in order to meet the requestin the market. Although the dimension of the electronic apparatus isreduced, the power and performance thereof have been enhanced to agreater extent. For example, communication modules and household and/orindustrial heat exchangers are provided therein with a number ofelectronic components. In operation, these electronic componentsgenerate a great amount of heat. Usually, a heat sink comprisingheat-dissipating pieces and a fan is used to dissipate the heat of theelectronic components and maintain the working temperature of theelectronic components in a normal range.

Recently, liquid-cooling technology has been widely used in personalcomputers, but not used in the aforesaid communication modules and thehouse and/or industrial heat exchangers. According to the liquid-coolingtechnology, the bulky heat-dissipating pieces are eliminated to reducethe dimension of the heat sink, and a working liquid is used to absorbthe heat of a heat source. In this way, the heat exchanger can be usedto exchange the heat absorb by the working liquid with external air.Further, the length of pipes can be modified properly to change theposition of the heat exchanger, so that the position of the heatexchanger may not be restricted by the space. Further, the liquid systemneeds a pump and a liquid tank to generate the circulation of theworking fluid. Thus, the pump and pipelines may suffer damage to causethe leakage of the working fluid. Although the liquid-cooling system hasthe above-mentioned problems, they are still preferred options for theheat dissipation of electronic elements in a personal computer becausethe dimension and external space of the personal computer are larger.

However, the communication modules and the household and/or industrialheat exchangers are made more and more compact in size, so that theliquid-cooling system is not suitable in such a compact space.Preferably, heat pipes or other small-sized heat sinks are still usedtogether with heat-dissipating fins to achieve a desiredheat-dissipating effect in these small-sized communication modules andthe household and/or industrial heat exchangers. In view of this, themanufacturers in this field continuously attempt to develop a betterheat-dissipating assembly.

In prior art, heat-dissipating elements such as heat pipes, vaporchambers are used for thermal conduction. When manufacturing the heatpipe or the vapor chamber, the internal walls of the heat pipe or thevapor chamber are formed with a sintered body serving as a wickstructure. To this end, metallic (such as copper) particles or powderare pressed and then sintered in a sintering furnace, so that the copperparticles or powder can be sintered as a porous wick structure. The wickstructure is configured to generate a capillary force so as to allow theworking fluid to flow through. However, because of this sintered wickstructure, the heat pipe or the vapor chamber has a certain thicknessand thus unable to be made as compact as possible. Alternatively,sintered cores, grids or grooves may be formed inside the vapor chamberfor generating a capillary force to drive the circulation ofliquid/vapor phase of the working fluid therein. However, manufacturingthe cores, grids and grooves in the vapor chamber involves a morecomplicated process and an increased cost.

Furthermore, in the above vapor chamber, the core is important becauseit serves as a path for allowing the condensed working fluid to flowthrough at high speed and maintains a sufficient capillary pressure toovercome the force of gravity.

Therefore, the conventional heat pipe or vapor chamber has the followingproblems.

(1) its manufacturing process is complex;

(2) it cannot be made compact enough;

(3) the cost is higher; and

(4) more working hours are needed.

SUMMARY OF THE INVENTION

In order to solve the above problems in prior art, an objective of thepresent invention is to provide a heat-dissipating assembly, which isapplied to a communication module and a household and/or industrial heatexchanger without providing any wick structure, and it has a reducedcost and size.

Another objective of the present invention is to provide aheat-dissipating assembly, which has a high heat-conducting efficiency.

In order to achieve the above objectives, the present invention providesa heat-dissipating assembly, which comprises: a body and a bottom plate.The body has a heat-absorbing portion and a heat-dissipating portion.The heat-dissipating portion has a plurality of heat-dissipating fins.The interior of the heat-absorbing portion has a chamber. The chamberhas a plurality of first guiding portions, a first communicating-holeset and a second communicating set. The first guiding portions areconstituted of a plurality of guiding bodies arranged at intervals. Onefirst flowing path is formed between adjacent two first guiding bodies.One end of the first flowing path is a free end connected to a freeregion. The first guiding portions and the first flowing pathscollectively define an evaporating region. The interior of the firstheat-dissipating fins forms a second flowing path. The second flowingpath and the heat-dissipating fins collectively define a condensingregion. The first communicating hole set and the second communicatinghole set are in communication with the evaporating region and thecondensing region. The bottom plate covers the chamber.

According to the heat-dissipating assembly of the present invention,each of the first flowing paths is formed between adjacent two firstguiding bodies. The working liquid contacting a heat source is vaporizedto become vapors, thereby generating a high pressure for driving thecirculation of the liquid/vapor phase of the working fluid. Thecondensing region is properly designed to have a low pressure. Thus, apressure gradient is generated between the high-pressure evaporatingregion and the low-pressure condensing region for driving thecirculation of the liquid/vapor phase of the working fluid. By thisarrangement, it is unnecessary to provide any wick structure to drivethe circulation of the working fluid for conducting the heat, so thatthe heat-conducting efficiency and the manufacturing cost can bereduced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view showing the heat-dissipatingassembly according to the first embodiment of the present invention;

FIG. 2 is an assembled perspective view showing the heat-dissipatingassembly according to the first embodiment of the present invention;

FIG. 3 is a cross-sectional view showing the heat-dissipating assemblyaccording to the first embodiment of the present invention;

FIG. 4 is a bottom view showing the heat-dissipating assembly accordingto a second embodiment of the present invention;

FIG. 5 a is a bottom view showing the heat-dissipating assemblyaccording to a third embodiment of the present invention;

FIG. 5 b is a bottom view showing the heat-dissipating assemblyaccording to another version of the third embodiment of the presentinvention;

FIG. 6 a is a bottom view showing the heat-dissipating assemblyaccording to a fourth embodiment of the present invention;

FIG. 6 b is a bottom view showing the heat-dissipating assemblyaccording to another version of the fourth embodiment of the presentinvention;

FIG. 6 c is a bottom view showing the heat-dissipating assemblyaccording to a further version of the fourth embodiment of the presentinvention;

FIG. 6 d is a bottom view showing the heat-dissipating assemblyaccording to a still further version of the fourth embodiment of thepresent invention;

FIG. 7 a is a bottom view showing the heat-dissipating assemblyaccording to a fifth embodiment of the present invention;

FIG. 7 b is a bottom view showing the heat-dissipating assemblyaccording to another version of the fifth embodiment of the presentinvention;

FIG. 8 is a bottom view showing the heat-dissipating assembly accordingto a sixth embodiment of the present invention;

FIG. 9 a is a bottom view showing the heat-dissipating assemblyaccording to a seventh embodiment of the present invention;

FIG. 9 b is a bottom view showing the heat-dissipating assemblyaccording to another version of the seventh embodiment of the presentinvention;

FIG. 9 c is a bottom view showing the heat-dissipating assemblyaccording to a further version of the seventh embodiment of the presentinvention; and

FIG. 9 d is a bottom view showing the heat-dissipating assemblyaccording to a still further version of the seventh embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

The above-mentioned objectives, structural and functional features ofthe present invention will be described with reference to preferredembodiments thereof and the accompanying drawings.

Please refer to FIGS. 1 to 3. As shown in these figures, the presentinvention provides a heat-dissipating assembly, which comprises a body 1and a bottom plate 2.

The body 1 has a heat-absorbing portion 11 and a heat-dissipatingportion 12. The interior of the heat-absorbing portion 11 has a chamber111. The chamber 111 has a plurality of first guiding portions 112, afirst communicating hole set 113, and a second communicating hole set114. The first guiding portion 112 is constituted of a plurality offirst guiding bodies arranged at intervals. One first flowing path 1122is formed between adjacent two first guiding bodies 1121. One end of thefirst flowing path 1122 is a free end connected to a free region 1124.The first guiding portions 112 and the first flowing paths 1122collectively define an evaporating region 13.

The bottom plate 2 correspondingly closed onto the chamber 111.

Each of the first guiding bodies 1121 may be an elongated rib. Theseelongated rib elongated ribs are arranged at intervals in a transversedirection. Each of the first flowing paths 1122 is formed betweenadjacent two elongated rib elongated ribs.

The heat-dissipating portion 12 has a plurality of heat-dissipating fins121. The interior of each heat-dissipating fin 121 has a second flowingpath 122. The second flowing path 122 and the heat-dissipating fin 121collectively define a condensing region 14. The first communicating holeset 113 and the second communicating hole set 114 are in communicationwith the evaporating region 13 and the condensing region 14.

Please refer to FIG. 4, which shows the heat-dissipating assemblyaccording to the second embodiment of the present invention. As shown inthis figure, some elements and the structural relationship between theseelements in the second embodiment are substantially equal to those inthe first embodiment, and thus the redundant description is omitted forsimplicity. The difference between the second embodiment and the firstembodiment lies in that the first guiding bodies 1121 are arranged atintervals in a longitudinal direction.

Please refer to FIGS. 5 a and 5 b, which show the heat-dissipatingassembly according to the third embodiment of the present invention. Asshown in this figure, some elements and the structural relationshipbetween these elements in the third embodiment are substantially equalto those in the previous embodiments, and thus the redundant descriptionis omitted for simplicity. The difference between the third embodimentand the previous embodiments lies in that the first guiding body 1121 isa rib. Each of the ribs has a first corner 1121 a, a first edge 1121 band a second edge 1121 c. The first edge 1121 b and the second edge 1121c intersect with each other at the first corner 1121 a. Each of thefirst flowing paths 1121 is formed between adjacent two ribs. A firstpitch 1125 is formed between adjacent two rows of the first guidingportions 112.

The first edges 1121 b may be arranged discontinuously and the secondedges 1121 c may be arranged discontinuously (as shown in FIG. 5 b).

Please refer to FIGS. 6 a, 6 b, 6 c and 6 d, which show theheat-dissipating assembly according to the fourth embodiment of thepresent invention. As shown in this figure, some elements and thestructural relationship between these elements in the fourth embodimentare substantially equal to those in the previous embodiments, and thusthe redundant description is omitted for simplicity. The differencebetween the fourth embodiment and the previous embodiments lies in thateach of the first guiding bodies 1121 of the first guiding portions 112is a rib, and these ribs surround to form a plurality of concentriccircles shown in FIG. 6 a, concentric triangles shown in FIG. 6 b,concentric rectangles shown in FIG. 6 c, or concentric irregular shapes.

Please refer to FIGS. 7 a and 7 b, which show the heat-dissipatingassembly according to the fifth embodiment of the present invention. Asshown in this figure, some elements and the structural relationshipbetween these elements in the fifth embodiment are substantially equalto those in the previous embodiments, and thus the redundant descriptionis omitted for simplicity. The difference between the fifth embodimentand the previous embodiments lies in that the first guiding body 1121 isan elongated rib. These elongated rib elongated ribs are arranged atintervals and extend outwards and radially from the evaporating region13. The first flowing path 1122 is formed between the adjacent two firstguiding bodies 1121.

As shown in FIG. 7 b, the first guiding bodies 1121 are discontinuouslyarranged in a longitudinal direction.

Please refer to FIG. 8, which shows the heat-dissipating assemblyaccording to the sixth embodiment of the present invention. As shown inthis figure, some elements and the structural relationship between theseelements in the sixth embodiment are substantially equal to those in theprevious embodiments, and thus the redundant description is omitted forsimplicity. The difference between the sixth embodiment and the previousembodiments lies in that a plurality pits 1126 is formed between thefirst guiding bodies 1121. Each of the pits 1126 is formed into oneshape selected from a group consisted of circles, squares, triangles,fish scales and other geometries. In the present embodiment, the pits1126 are formed into a fish-scale shape, but are not limited thereto.

Please refer to FIGS. 9 a, 9 b, 9 c and 9 d, which show theheat-dissipating assembly according to the seventh embodiment of thepresent invention. As shown in this figure, some elements and thestructural relationship between these elements in the seventh embodimentare substantially equal to those in the previous embodiments, and thusthe redundant description is omitted for simplicity. The differencebetween the seventh embodiment and the previous embodiments lies in thateach of the first guiding portions 1121 of the first guiding portions112 is a protrusion. These protrusions are arranged at intervals in thetransverse direction and the longitudinal direction. Each of the firstflowing paths 1122 is formed between the adjacent two protrusions.

The protrusion is formed into a shape selected from a group consisted incircles as shown in FIG. 9 a, triangles as shown in FIG. 9 b, rectanglesas shown in FIG. 9 c, and rhombuses as shown in FIG. 9 d.

Please refer to FIGS. 1 to 9 d again. The first to seventh embodimentsof the present invention provides an improved cooling technology byusing the heat-dissipating assembly of the present invention and thecirculation of liquid/vapor phases of a working fluid. The circulationof the working fluid is automatically driven by means of the pressuregradient, and the working fluid may be pure water, methyl alcohol,acetone, R134A and other suitable coolants. The chamber 111 of theheat-dissipating assembly is made vacuum, and the working fluid isfilled in the chamber 111. The saturated temperature of the workingfluid is in a range of 20 to 30° C. After vapor bubbles 2 are formed andcollected in the evaporating region 12, these vapor bubbles 2 flowthrough the free region 1124 to release their pressure, therebygenerating the pressure gradient for driving the circulation ofliquid/vapor phase of the working fluid. Further, in the condensingregion 14, the specific volume of the condensed working fluid increasesabruptly to generate a negative pressure, thereby facilitating thecirculation of liquid/vapor phase of the working fluid.

The condensed working fluid in the condensing region 14 is driven by thepressure gradient to flow back to the evaporating region 13. By means ofa high coefficient of heat convection, the temperature gradientthroughout the heat-dissipating assembly becomes more uniform and thethermal resistance is reduced.

That is, the heat generated by heat-generating elements (not shown) isconducted into the evaporating region 13 of the body 1, and then intothe first flowing paths 1122 of the evaporating region 13. A portion ofthe working fluid is vaporized to form vapor bubbles in the firstflowing paths 1122. The buoyance of the vapor bubbles makes them flowinto the condensing region 14 to release their latent heat. Thecondensed working fluid flows back to the evaporating region 13 by meansof a downward force of gravity. As a result, the condensing workingfluid absorbs heat again in the evaporating region 13 whose surface isbrought into thermal contact with the heat-generating elements (notshown).

Although many manufacturers in this field propose various kinds ofliquid-cooling technologies, especially an active liquid-coolingtechnology in which the circulation of the working fluid is driven by apump, such an active liquid-cooling technology has problems that thepump and associated valves may breakdown to affect the lifetime of thewhole liquid-cooling system. In comparison with prior art, the presentinvention has the following advantageous features. The heat-dissipatingassembly of the present invention utilizes the pressure gradient toautomatically drive the circulation of liquid/vapor phase of the workingfluid, so that no pump and wick structure are used in the presentinvention. Thus, the breakdown of the pump and the manufacturing processof the wick structure are eliminated, thereby saving energy and avoidnoises generated by the operation of the pump.

Although the present invention has been described with reference to theforegoing preferred embodiments, it will be understood that theinvention is not limited to the details thereof. Various equivalentvariations and modifications can still occur to those skilled in thisart in view of the teachings of the present invention. Thus, all suchvariations and equivalent modifications are also embraced within thescope of the invention as defined in the appended claims.

1. A heat-dissipating assembly, comprising: a body having aheat-absorbing portion and a heat-dissipating portion, theheat-dissipating portion having a plurality of heat-dissipating fins,the interior of the heat-absorbing portion having a chamber, the chamberhaving a plurality of first guiding portions, a first communicating-holeset and a second communicating set, the first guiding portions beingconstituted of a plurality of first guiding bodies arranged atintervals, at least one first flowing path being formed between adjacenttwo first guiding bodies, at least one end of the first flowing pathbeing a free end connected to a free region, the first guiding portionsand the first flowing paths collectively define an evaporating region,the interior of the first heat-dissipating fins having a second flowingpath, the second flowing path and the heat-dissipating fins collectivelydefine a condensing region, the first communicating hole set and thesecond communicating hole set being in communication with theevaporating region and the condensing region; and a bottom platecorrespondingly closed onto the chamber.
 2. The heat-dissipatingassembly according to claim 1, wherein each of the first guiding bodiesis an elongated rib, the ribs are arranged at intervals in a transversedirection, the first flowing path is formed between the adjacent twoelongated ribs.
 3. The heat-dissipating assembly according to claim 2,wherein the first guiding bodies are arranged at intervals in alongitudinal direction.
 4. The heat-dissipating assembly according toclaim 1, wherein each of the first guiding bodies is a rib having afirst corner, a first edge and a second edge, the first edge and thesecond edge intersect with each other at the first corner, the firstflowing paths are formed between the adjacent two ribs respectively, afirst pitch is formed between adjacent two rows of the first guidingportions.
 5. The heat-dissipating assembly according to claim 4, whereinthe first edges are arranged discontinuously, and the second edges arearranged discontinuously.
 6. The heat-dissipating assembly according toclaim 1, wherein each of the first guiding bodies of the first guidingportions is a rib, and these ribs surround discontinuously to form ashape selected from any of concentric circles, concentric triangles,concentric rectangles, and concentric irregular shapes.
 7. Theheat-dissipating assembly according to claim 1, wherein each of thefirst guiding bodies is an elongated rib, the ribs are arranged atintervals and extend radially and outwards from the evaporating region,the first flowing path is formed between the adjacent two first guidingbodies.
 8. The heat-dissipating assembly according to claim 7, whereinthe first guiding bodies are discontinuously arranged at intervals in alongitudinal direction.
 9. The heat-dissipating assembly according toclaim 1, wherein a plurality of pits is formed between the first guidingbodies.
 10. The heat-dissipating assembly according to claim 9, whereineach of the pits is formed into a shape selected from any of circle,square, triangle, and fish-scale shape.
 11. The heat-dissipatingassembly according to claim 1, wherein each of the first guiding bodiesof the first guiding portions is protrusion, and these protrusions arearranged at intervals in both a transverse direction and a longitudinaldirection, each of the first flowing paths is formed between adjacenttwo protrusions.
 12. The heat-dissipating assembly according to claim11, wherein each of the protrusions is formed into a shape selected fromany of a circle, triangle, rectangle, rhombus, and other geometries.